Traditional headrests used to equip motor vehicle seats are made of a synthetic foam cushion, covered with a slipcover structure made of cloth, synthetic material or leather, and include a stiff insert that enables two parallel anchor rods to get fitted into the housing sleeves installed on the upper portion of the equipped seat.
In some headrest structures, the distance between the anchor rods cannot be adjusted; as a result, during the manufacturing process itself, it becomes necessary to provide different versions of the headrests, depending on the distance between the housing sleeves in the seat intended to receive it.
In other known models, as described for example in U.S. patent application Ser. No. 6,022,078, German Patent Application 196 52 591, or even French Patent Application 2 796 017, the distance between the anchor rods is variable, but the internal fitting means by way of which these rods are adapted to this variability, are relatively complex.
Furthermore, as can be seen in U.S. patent application Ser. No. 5,713,633 or German Patent Application 196 01 582, some of the more recent headrest models are equipped with monitors, particularly of the liquid crystal type, for DVD players, game consoles and the like, that are integrated into the rear face of the headrests so as to be accessible from the rear seats of the vehicle. The presence of these monitors further complicates the integrated fitting structure of the headrest.